Arrangement for signalling movement of a member by means of a magnet movable past a reed switch



May 20, 1969 F. SPIROCH ET AL 3,445,796

ARRANGEMENT FOR SIGNALLING MOVEMENT OF A MEMBER BY MEANS OF A MAGNET MOVABLE PAST A REED SWITCH Filed 001;. 21. 1966 IN VENTORS Franz, Jj'urock sj'yh'ld la!!! am; has

United States Patent US. Cl. 335205 8 Claims ABSTRACT OF THE DISCLOSURE An arrangement for signalling the movement of a member by moving a magnet fixed to the member past a gas switch including a gas-tight envelope and a pair of resilient switch blades of magnetizable material in the envelope, which blades have overlapping ends normally spaced from each other and moving in engagement with each other when subjected to the-magentic field of the magnet during movement of the latter from a rest position to an active position closely adjacent to the overlapping ends of the switch blades so that the movement of the member may be signalled by means in circuit with the gas switch.

The present invention relates to an arrangement wherein a gas switch is connected with a supporting plate of insulating material on which circuit means are printed.

The invention is intended for responding to the movement of a member, or an apparatus, preferably of an apparatus in which movement of a member is signalled by means of a gas switch.

The term gas switch as used in the present application is to be understood as switch which includes a gas-tight envelope which may be evacuated or which may be filled with an inert gas and in which a pair of contact means are located constructed to normally stay in an open position and movable from said open to a closed position when subjected to a magnetic field. The contact means preferably comprise a pair of resilient blades of magnetizable material extending longitudinally through the envelope and having overlapping inner ends normally spaced from each other and moving in engagement with each other to close the switch when a magnetic field acts on the overlapping ends of the blades. The outer ends of these blades extend gas-tightly scaled through and beyond the opposite closed ends of the envelope and are adapted to be connected to the circuit means.

Such gas switches are advantageously used for signalling the position or movement of a member, since such switches are subjected to very little wear and will therefore operate trouble-free for extended time periods. Furthermore, operation of these switches requires only relatively small magnetic fields. In. order to signal movement of a member by means of a gas switch of the aforementioned type, the member carries a small permanent magnet or a soft iron member magentized during movement of the member and the permanent magnet or the member of soft iron carried by the movable member are arranged in such a manner so as to be closely adjacent the overlapping ends of the contact blades of the switch when the member reaches during the movement thereof an end position which is to be indicated.

The components for such an arrangement require relatively little space, however, considerable diificulties are encountered in properly supporting and connecting the gas switch, especially when a great number of such ar- 3,445,796 Patented May 20, 1969 ice rangements are to be mounted closely adjacent to each other.

It is an object of the present invention to provide for an arrangement of the aforementioned type in which the gas switch is mounted and connected to the printed conductor means in a very simple manner.

It is a further object of the present invention to provide support means for a gas switch in an arrangement of the aforementioned type which require very little space and which lend themselves conveniently to mass fabrication.

With these objects in view, the aforementioned arrangement for responding to the movement of a member mainly comp-rises a gas switch including a gas-tight envelope, a pair of contact means in the envelope constructed to normally stay in open poistion and movable from the open to a closed position when subjected to a magnetic field, the contact means having outer ends extending gas-tightly sealed through and beyond the envelope, support means for supporting the gas switch and including a plate of insulating material provided with printed circuit means to which the outer ends of the gas switch are connected, for instance by soldering, and a member having a magnet portion arranged for movement between a rest position and an active position in which the magnet portion of the member is closely adjacent the pair of contact means so that the magnetic field produced by the magnet portion causes movement of the contact means to the closed position, whereby movement of the aforementioned member to the active position may be responded by means connected to the circuit means printed on the plate, said outer ends of said gas switch being soldered to said printed circuit on said plate for support 'by said plate and for electrical connection to said printed circuit. Preferably, the circuit means on the plate of insulating material are printed circuits and the plate is preferably of rectangular configuration formed with an elongated cutout extending from one longitudinal edge of the plate into the latter, and the gas switch is located in the cutout while the aforementioned member is arranged for reciprocating movement between the rest and the active position thereof substantially parallel to the one edge of the plate.

The plate of insulating material is preferably provided in the region of one end thereof with attaching means for attaching the plate to a frame or the like so that a plurality of such plates carrying gas switches may be arranged closely adjacent to each other.

Preferably, the arrangement includes also a guard member extending substantially in the plane of the plate of insulating material closely adjacent at least along one longitudinal edge of the plate which is opposite the longitudinal edge from which the aforementioned cutout extends into the plate. This guard member may also extend about the end of the plate which is opposite the end thereof in which the attaching means are provided. This guard member provided to protect the plate of insulating material against outside forces is formed from rigid material, preferably metal, and the guard member may be arranged as a frame connected to outer edges of the plate of insulating material or be located slightly spaced from outer edges of the plate and out of contact with the latter. Depending on the manner in which the magnetic field provided by the magnetic portion of the movable member co-operates with the contact means of the switch and further dependent on the kind of the magnetic field, the material from which the guard member is formed may either be non-magnetic or magnetizable material, such as for instance soft iron.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. 1 is a schematic side view of one arrangement of the aforementioned kind according to the present invention; and

FIG. 2 is a modification of the arrangement shown in FIG. 1.

Referring now to the drawing, and more specifically to FIG. 1 of the same, it will be seen that the arrangement according to the present invention for responding to or signalling movement or position of a movable member mainly comprises a gas switch 21 including a gastight elongated envelope 21' and a pair of contact means 19 and 20 in theenvelope constructed to normally stay in an open position and movable from the open to a closed position when subjected to a magnetic field. The contact means 19 and 20 are preferably in the form of resilient blades of magnetizable material having inner overlapping ends 19 and 20" normally spaced transversely from each other and outer ends 19" and 20" extending gas-tightly sealed through and beyond the envelope 21.

The support means for supporting the gas switch 21 comprises according to the present invention a plate of insulating material and preferably rectangular configuration, and provided with a preferably rectangular cutout 22 extending from one longitudinal edge of the plate 10 into the latter; and the elongated envelope 21' of the gas switch 21 is located in the cutout 22 of the plate 10. Circuit means are provided on the plate 10* to which the outer ends 19" and 20" of the blades of the gas switch 21 are connected. The circuit means preferably comprise a pair of printed circuit portions 11 and 12 and the circuit portion 11 extends between a pair of bores 15 and 17 through the plate 10, whereas the circuit portion 12 extends between bores 16 and 18. The outer ends 19 and of the blades of the gas switch 21 extend respectively into the bores 17 and 18 and are connected to the respective ends of the printed circuits 11 and 12 by soldering material filling the bores 17 and 18. The outer ends of the printed circuits 11 and 12 may be connected to a signalling device by conductors not shown in the drawing soldered in the bores 15 and 16 to the outer ends of the printed circuits 11 and 12. The plate 10 is formed in the region of the left end thereof, as viewed in FIG. 1, with an attaching means which may include a pair of additional bores 13 and 14 through which attaching pins or screws, not shown in the drawing, may extend to fixedly connect the plate 10 to a frame or the like, not shown in the drawing. If a plurality of plates 10 and gas switches 21 supported thereon are to be mounted closely adjusted to each other attaching pins may extend through the bores 13 and 14 and the plates may be held spaced from each other by appropriate annular spacers about the attaching pins and between adjacent plates.

The member 24, the position of which is to be indicated by the gas switch 21 is arranged for reciprocating movement in the direction of the arrow 23 adjacent to and substantially parallel to the longitudinal edge of the plate 10 from which the cutout 22 extends into the plate 22. The member 24 carriers, in the arrangement shown in FIG. 1, a small permanent magnet fixedly connected thereto, which projects to one side of the elongated member partly into the cutout 22 so that the inner end of the permanent magnet 25 is arranged very close to the envelope 21 of the gas switch. When the member 24 and the permanent magnet 25 thereon is moved to a position in which the inner end of the permanent magnet 25 is opposite the overlapping ends 19' and 20' of the blades of the switch 21, the blades will be magnetized and the switch closed so that this position of the member 24 may be indicated by signal means of any known type connected to the outer ends of the printed circuit portions 11 and 12.

A guard member 26 of rigid material may be provided to protect the plate 20 and the gas switch 21 carried thereby and the guard member 26 may extend substantially in the plane of the plate 10 for instance along one longitudinal side edge and one front edge of the plate 10, and the guard member 26 may be connected in any convenient manner, not shown in the drawing, to a frame or the like on which the plate 10 is also mounted. The materials of which the guard member 26 is formed will depend from the kind of magnetic field used to magnetize the blades 19 and 20 of the switch 21. When, as described above, a permanent magnet 25 carried by the member 24 is used to magnetize the blades of the switch 21, the magnetic field should be restricted as far as possible to the region of the permanent magnet 25 and the inner ends of the contact blades, and in this case the guard member 26 is preferably formed from non-magnetic material, for instance aluminum, to avoid shunting of the magnetic field of the permanent magnet 25. Such an aluminum guard member will also shield the aforementioned arrangement against electric fields.

A modification of the arrangement above described in connection with FIG. 1 is shown in FIG. 2. The arrangement shown in FIG. 2 differs from that illustrated in FIG. 1 only by the means for producing a magnetic field to magnetize the blades of the gas switch 21 and thereby close the circuit in which the switch is located and by the construction of the guard member. The movable member 29, the position of which should be indicated by the disclosed arrangement, comprises in the embodiment illustrated in FIG. 2 the armature or core of an electromagnet having a coil 27 located laterally of one end of the plate 10. The armature 29 which is formed preferably from soft iron is reciprocated in a known manner during energizing or de-energizing of the coil 27 in the direction of the arrow 23 along the longitudinal edge of the plate 10 in which the cutout 22 is formed. The armature 29 carries a member 28 of soft iron fixedly connected thereto and projecting to one side thereof into the cutout 22 of the plate 10 so that during reciprocation of the armature 29 the member 28 may move opposite the inner overlapping ends of the blades of the switch 21 so that the magnetic field produced during energizing of the coil 27 in the armature 29 and in the soft iron member 28 will at least partly extend through the overlapping ends of the blades of the switch 21 so that the blades are likewise magnetized and the overlapping ends thereof brought into engagement with each other to thereby close the circuit in which the switch 21 is arranged. In this modification the guard member 26 is preferably made also from magnetizable material, for instance soft iron and the guard member 26 extends with an end portion 30 about the right end, as viewed in FIG. 2, of the plate 10 into proximity of the right blade 19 of the switch 21 to produce between the pole 28 and the armature 29 a magnetic stray field which, when the pole 28 is located in the region of the overlapping ends of the blades 19 and 20, will extend also at least partly over the inner portion of the blade 20. The guard member 26 when made of magnetizable material will also protect the switch 21 against the influence of external magnetic fields not produced by the electromagnet 27, 29 co-ordinated with the switch 21.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of arrangements for responding to the movement of a member differing from the types described above.

While the invention has been illustrated and described as embodied in an arrangement for signalling the movement of a member and using a magnetically operated gas switch, it is not intended to be limited to the details shown,

since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are contended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In an arrangement of the character described, in combination, a gas switch including a gas-type envelope, a pair of contact means in said envelope constructed to stay in one position and movable from the one to another position when subjected to a magnetic field, said contact means having outer ends extending gas tightly sealed through and beyond said envelope; support means for supporting said gas switch and including a plate of insulating material provided with circuit means, said plate of insulating material being formed with an elongated cutout extending from one edge of said plate to the latter and said gas switch being located in said cutout, said outer ends of said contact means being electrically and mechanically connected to said circuit means; a member arranged for reciprocating movement adjacent said one edge of the plate and having a magnet portion movable during reciprocation of said member between a rest position and an active position in which said magnet portion thereof is closely adjacent to said pair of contact means so that the magnetic field produced by said magnet portion causes movement of said conductor means from one to the other of the positions thereof, whereby movement of said member to said active position may be indicated by means connected to said circuit means on said plate; and a metal guard member extending substantially in the plane of said plate closely adjacent at least along a longitudinal edge of the latter which is opposite said one longitudinal edge so as to shield said contact means from the influence of extraneous fields.

2. In the arrangement as defined in claim 1, wherein said pair of contact means comprise a pair of resilient blades of magnetizable material having outer ends extending gas-tightly sealed through and beyond said envelope, and inner overlapping ends normally spaced from each other and movable in engagement with each other when said inner overlapping ends are subjected to a magnetic field.

3. In an arrangement as defined in claim 2, wherein said circuit means on said plate of insulating material are printed circuits.

4. In an arrangement as set forth in claim 3, wherein said plate of insulating material is substantially rectangular and wherein said cutout extending from one longitudinal edge of said rectangular plate is likewise rectangular, said printed circuits include two circuit portions arranged in the region between opposite and edges of said plates and opposite side edges of said cutouts and said plate being formed at the opposite ends of each circuit portion with a bore therethrough, the outer end of each blade extending into the bore at one end of the respective circuit portion and being connected thereto by solder in said bore.

5. In an arrangement as defined in claim 1, wherein said plate is provided in the region of one end thereof with attaching means, said guard member extending also about the other end of said plate.

6. In an arrangement as defined in claim 5, wherein said guard member is formed from non-magnetic material.

7. In an arrangement as defined in claim 5, wherein said guard member is formed from aluminum.

8. In an arrangement as defined in claim 5, wherein said guard member is formed from magnetic material, preferably soft iron.

References Cited UNITED STATES PATENTS 3,043,021 7/1962 Thompson 317101 XR 3,177,315 3/1965 Clare.

3,330,016 7/1967 Smith et al 335-205 XR 3,320,559 5/1967 Morrison 335-151 BERNARD A. GILHEANY, Primary Examiner.

R. N. ENVALL, JR., Assistant Examiner.

US. Cl. X.R. 

